SE,B, 422,491 (GKN-Stenman) and U.S. Pat. No. 4,393,673 (Widen) describe a combination of this kind in which the key, in addition to a web part, has a side part which includes a coded surface having code parts or shoulders for engagement with an edge part of one end of the respective pin tumblers and with transition parts which extend in the direction of the long axis of the key between mutually adjacent code shoulders. The code shoulders and transition parts of the side part of the key include parts of surfaces which are described by a point or by a line or curve provided with an end point which rotate with said point for said end point at a given distance from a point on an axis which extends generally parallel with the axes of the pin tumblers, said axes moving continuously or discontinuously in a plane that extends through the pin axes or in a plane which is generally parallel therewith.
The pin tumblers may coact with spring-activated top tumblers or may themselves be activated and provided with waisted parts for coaction with outwardly projecting shoulders on a side-bar.
The side-bar is spring-biased outwardly from the cylinder, into engagement with a recess in the lock housing, this recess being configured to urge the side-bar into the cylinder plug as it rotates, subsequent to having inserted the correct key into an operative position in the plug. The side-bar includes a number of lugs having rounded engagement surfaces which coact with waisted parts of the side-bar. In manufacture, the coded surfaces and the intermediate transition surfaces must be produced very accurately, and consequently the cylinder lock taught by this prior publication is comparatively expensive to produce.
U.S. Pat. No. 5,067,335 and SE,B, 455,801 (Widen) describe another type of lock which is provided with a side-bar and the pin tumblers of which are guided forcibly in different directions of rotation and have a form which makes the lock expensive to produce.
U.S. Pat. No. 3,264,852 (Gysin) teaches a cylinder lock with which there is used a key which is provided on the side surfaces thereof with grooves which, when the key is inserted to an operative position in the plug, coact with tumblers that have outwardly projecting pins for engagement in respective grooves. The tumblers of this lock do not coact with a side-bar. Moreover, the pins on the tumblers are subjected to a relatively high degree of wear, which is liable to jeopardize the function of the cylinder lock after long-time use.
Another example of the standpoint of techniques is found in DE,C, 575,828 (Albert Brun in Paris).